foo.cc:2:16: error: expected identifier before ';' token
 using namespace;
                ^
foo.cc: In function 'int main()':
foo.cc:7:2: error: 'cin' was not declared in this scope
  cin>>x>>y>>z;
  ^~~
foo.cc:7:2: note: suggested alternative:
In file included from foo.cc:1:0:
/usr/include/c++/7/iostream:60:18: note:   'std::cin'
   extern istream cin;  /// Linked to standard input
                  ^~~
foo.cc:9:2: error: 'coat' was not declared in this scope
  coat<<a;
  ^~~~
foo.cc:9:2: note: suggested alternative: 'char'
  coat<<a;
  ^~~~
  char

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